Bituminous composition



Patented Apr. 27, 1943 BITUMINOUS COMPOSITION James M. Johnson and Earl C. Brown, New York,

N. Y., asslgnors to Nostrip, Inc., a corporation of Delaware No Drawing. Application March 1, 1941, Serial No. 381,398

14 Claims. (Cl. 106-269) This invention relates to a bituminous composition. More particularly the invention relates to a composition comprising an asphaltic material, an insoluble soap, and an emulsifier adapted when in contact with wet aggregate to promote formation of emulsions of the water-in-oil type and lasting adherence of the composition to the aggregate. t

The invention is particularly adapted for use in connection with paving compositions and will be illustrated by description relating thereto.

Improvement of the contact between wet stony aggregate, such as broken stone or gravel, with bituminous paving compositions has received a great deal of attention and numerous proposals have been made for effecting such improvement. There remains, however, the need of an economical composition adapted to adhere not only quickly but also durably to aggregate incorporated in wet condition and to show desired resistance to loss of plasticity of the composition on aging under-conditions of use.-

The present invention provides such a come position. Briefly stated, the invention comprises a bituminous composition characterized by thoroughness of contact and adherence to stony aggregate incorporated in wet condition, the composition containing an asphalt-1c material and a mixture of an insoluble soap and an emulsifier, and the emulsifier being one that when in contact with the insoluble soap and water, is effective in producing emulsions of the water-in-oil type.

In the preferred embodiment, the invention comprises the use as emulsifier of a higher fatty acid derivative containing an NH: group in the form of the acid amide and suitably partly also in the form of an amine. The invention includes also the method of making bituminous compositions of the kind described. a

In general, there is formed an anhydrous mixture of the bituminous material, a water insoluble soap, and emulsifier of the kind described, the proportion of soap and emulsifier being minor as compared to .the amount of bituminous material present. Such a composition applied to aggregate is highly resistant to stripping of the composition from the aggregate under severe conditions of test or use.

As the bituminous material, there is used to advantage one of the common grades of asphaltic .material, such as natural asphalt or petroleum still residues of paving grade. There may be used also the plastic residues from coal tar distillation.

\ As the insoluble soap, there is used to advantage the zinc oxide soap of tall oil, a fatty acid containing by-product of the paper industry that contains a large proportion of abietic acid and a lesser proportion of other higher fatty acids. In place of the tall .011, there may be used oleic acid, ricinoleic acid, linoleic acid, the mixture of acids derivable by'hydrolysis of cottonseed oil, corn oil,

or fish oil, or like acids. In place of the zinc soap, there may be used the corresponding soaps of aluminum, iron, calcium or other multivalent metal ordinarily utilized in the making of waterrepellent soaps. The zinc'soaps, however, are particularly effective for the purpose and are preferred.

The proportion of zinc oxide or other metal compound, used to react with the fatty acids in sufficient to neutralize a large part and advantageously all of the fatty acids. Particularly good results are obtained when the proportion used is substantially in excess of the fatty acids. Thus, when zinc oxide is used as a source of the multivalent metal it may be used in the proportion of about 10 to 30 parts for parts of the tall oil or equivalent amount of other fatty acids.

When metal compounds other than zinc oxide are used, they should be used in proportion equivalent to the zinc oxide which they replace, that is, equivalent to about 10 to 30 parts of zinc oxide for each 100 parts of the fatty acids.

In making insoluble soaps of metals whose oxides do not react readily .with higher fatty acids, the fatty acids may be first converted to sodium soaps which are then treated with watersoluble salts of the multivalent metals, as, for example, aluminum or ferric sulfate or chloride, in the presence of water. The sodium salt produced as a by-product is removed by repeated washing. The insoluble soap so made is then thoroughly dried, by warming to cause evaporation of water present.

Particularly good results in lasting adherence of the bituminous composition to aggregate have been obtained when the emulsifier is an amide examples.

the radical of a higher fatty acid. Such an amine is made to advantage by the reaction of ethylene diamine, diethylene triamine, triethylene pentamine, or other polyamine with a fatty acid in proportion inadequate to neutralize all of the amine groups. Thus, there may be made an amine that is satisfactory for the present purpose by the interaction of 1 molecular proportion of oleic acid and 1 molecular proportion of ethylene diamine. With the triamines, as a further example, there may be used two molecular proportions of the fatty acid for 1 molecular proportion of the triamine. Products so made contain an unreacted amine group,

The amide, and amine if used, should be liquid at the temperature of pouring of the bituminous composition as applied in paving and should be soluble or readily dispersible in the said composition.

Particularly satisfactory emulsifiers of this general type are those known as Nopco 2179-3, an oleyl amide. Another very satisfactory emulsifier is the oxyalkyl (say oxymethyl, oxyethyl, or oxybutl) amide of a fatty acid of the kind described. A suitable amine is Nopco C. V. T., which includes the reaction product of oleic acid with ethylene 'diamine in equimolecular proportions.

Compositions and the method that have been found to be particularly satisfactory are illustrated in further detail in the following specific Example I One hundred parts of talloil are warmed to about 325 F. and twenty-eight parts of zinc oxide are incorporated with thorough stirring, proportions here and elsewhere herein being expressed as parts by weight. The resulting mixture including zinc soaps of the acids of talloil and a substantial excess of zinc oxide is maintained at an elevated temperature and stirred until practically all water formed in the reaction has been expelled and the remaining material is made substantially anhydrous.

The soap so made is mixed with an oleic acid amide, the amide being used to advantage in the proportion of about 2 to 8 parts for 100 parts of the soap. Preferably the amide is incorporated into the talloil before the zinc oxide is added, so that uniform incorporation may be made conveniently.

The mixture of soap and emulsifier so made is then thoroughly blended into bituminous material, either with or without the use of usual cut-back solvents. It is a feature of my invention, that the emulsifier and soap mixture has the power of emulsifying water in semi-solid asphalt without cutting with a solvent. The proportion of the mixed soap and emulsifier need not be large, about 0.5 to parts of the mixture for 100 parts of bituminous material being sufficient and the exact proportion selected depending upon the extent of the emulsifying effect desired from the use of the mixed soap and emulsifier and thoroughness of adherence to the aggregate on aging. With most types of aggregate, 1 to 2 parts of the mixture for 100 parts of asphalt are adequate.

Example [I gradient being of the type discussed in detail above, as, for example, the Nopco, C. V. T.

While the compositions of both Examples I and II are satisfactory in giving contact and adherence of the bituminous composition to aggregate initially incorporated in wet condition, I have found that the composition of Example 11 is superior in giving quicker contact and more lasting adherence with certain types of aggregate. With some types of aggregates characterized by relatively low resistance to wetting by asphalt or the like, I may omit the emulsifiers of Examples I and II (1. e. the amide and amine may be omitted) provided zinc soap is used and the composition contains a'substantial excess of zinc oxide, over the tatty acid component.

The bituminous compositions made as described are substantially anhydrous, the 'raw materials used in making the compositions containing no appreciable amounts of water.

In using bituminous compositions of the kind described, it is advantageous to treat the aggregate with a small proportion of lime, say, with hydrated lime in the proportion of about onehalf to 1 part for 100 parts of the aggregate, before the bituminous composition is applied. When the aggregate is so treated, adhesion of the bituminous composition occurs at once.

In making my new composition in a usual type of traveling plant, the mixture of the bitumen, insoluble soap and emulsifier, and thelimetreated aggregate are placed in a pugmill, The mixture is agitated and heated to approximately 600 F., to lower the viscosity of the bitumen composition. Substantially a perfect coating of the aggregate and adhesion is secured in a few minutes, regardless of whether the aggregate is initially supplied wet or dry or even frozen. The coated aggregate is then discharged from the pugmill directly into a conventional spreader and finishing unit equipped with a torch which maintains a temperature of about 300 F. or so. The coated aggregate is then placed in the pavement.

Tests show that the finished composition is characterized by strong adherence of the bituminous composition to the aggregate and also that the bituminous composition itself remains of high ductility and plasticity on aging. When inch aggregate is coated with my improved composition of the kind described in Examples I and II, allowed to cure, and then submerged in distilled water for 24 hours, the amount of stripping which results is not greatly in excess of 1 per cent. The results of the standard Nicholson test are significant, also. When the inch aggregate is coated with the composition, cured for 24 hours, and then tumbled in water for 15 minutes at F., 45 minutes at F., and 15 minutes at F., there is practically no stripping, when the aggregate used is either hydrophilic or hydrophobic. Furthermore, the asphalt or like bituminous material in the composition remains ductile and plastic over a long period of time, as distinguished from the loss of life and embrittling which are experienced in certain conventional asphalt compositions on long exposure to the oxidizing influence of the atmosphere.

It is to be understood that the details given are for the purpose of illustration and that variations within the spirit of the invention are intended to be included within the scope of the appended claims.

What we claim is: p 1. A bituminous composition characterized by thoroughness of contact; and lasting adherence to stony aggregate incorporated in wet condition, the composition being substantially anhydrous and comprising an asphaltic material, a water insoluble soap, and an amide of a higher fatty acid constituting an emulsifier adapted, when in contact with the insoluble soap and water, to cause the formation of emulsions of the water-in-oil type.

2. A bituminous composition characterized by thoroughness of contact and lasting adherence to stony aggregate incorporated in wet condition, the composition being substantially anhydrous and comprising an asphaltic material, a water insoluble soap, and an emulsifier com pound containing the radical of a higher fatty acid and an amine group constituting an emulsifler adapted to cause; when in contact with the insoluble soap and water, the formation of emulsions of the water-in-oil type.

3. A bituminous composition characterized by thoroughness of contact and lasting adherence to-stony aggregate incorporated. in wet condition, the composition being substantially anhydrous and comprising an asphaltic material, a water insoluble soap, and a mixture of a higher fatty acid amide and an emulsifier compound containing a higher fatty acid radical and an amine group constituting an emulsifier adapted, when in contact with the insoluble soap and water, to cause the formation of emulsions of the water-in-oil type.

4. A substantially anhydrous paving composi tion comprising a major proportion of asphalt and a minor proportion of a mixture of a multivalent metal salt of oleic acid and oleamide, the proportion of the oleamide being substantially less than the proportion of the said salt.

5. A substantially anhydrous paving composition comprising a major proportion of'asphalt and a. minor proportion of a mixture of a multivalent metal salt of oleic acid and an oxyalkyl fatty acid amide, the proportion of the amide being substantially less than the proportion of the said salt.

6. A substantially anhydrous paving composition comprising a major proportion of an asphaltic material and a minor proportion of a mixture of a multivalent metal soap and an emulsifier, the emulsifier being the product of the reaction of a. polyamine with a higher fatty acid in proportion substantially less than that adequate to react with all the amine groups of of the amine groups of the diamine, so as to produce a compound containing the radical of a higher fatty acid and an amine group.

8. A paving composition comprising asphalt and the reaction product of talloil with zinc oxide, the said reaction products having the property, when in contact with water, of-promoting the formation of emulsions of the waterin-oil type.

9. A paving composition as described in claim 8, the zinc oxide being in substantial excess of the amount equivalent to the talloil and promoting contact and adherence of the composition to aggregate incorporated in wet condition and the composition including an emulsifier consisting of an amide of a higher fatty acid.

10. A paving composition comprising asphalt' and a multivalent metal soap of the fatty acids of talloil and an emulsifier consisting of an amide of a higher fatty acid, the said soap and amide having the property, when in contact with water, of promoting the formation of emulsions of the water-in-oil type.

11. A paving composition as described in claim 1, the emulsifier being present in the proportion of about 0.5 to 5 parts for part of the asphaltic material.

12. A paving composition as described in claim 1, the emulsifier being present in the proportion of about 0.5 to 5 parts for 100 parts of the asphaltic materialand the composition containing about 2 to 8 parts of the higher fatty acid amide for 100 parts of the said water-insoluble soap of the multivalent metal with the higher fatty acid.

13. A paving composition comprising a stony aggregate and a bituminous composition of the kind described in claim 1 extending between and adheringstrongly to the said aggregate.

14. A composition as described in claim 1 including admixed lime, the lime serving to promote adhesion of the bituminous composition to the said aggregate.

- JAMES M. JOHNSON.

EARL C. BROWN. 

